This is a revised application for a competing continuation. Previous case-control and cross-sectional studies have shown an association between extracranial carotid artery intimal-medial thickening (ECIMT) and coronary artery disease (CAD). The present proposal is to complete a longitudinal study to determine whether the impression of rapid progression of ECIMT in patients with CAD compared to control subjects without CAD is correct. A second purpose of the study is to quantify the magnitude of the overall effect as well as the segment specific effect in men and women as it is influenced by baseline risk factors and baseline ECIMT. Another question of importance is whether rapid progression of ECIMT leads to reduction of the lumen diameter. Recent studies by this group have suggested that there may be a complex relationship between ECIMT and lumen size. The proposal is for completion of a longitudinal study of a group of men and women with and without CAD for a total of 3 years of follow-up. The first Specific Aim is to obtain 3 year progression rates of ECIMT in the previously accessed cohort of 280 subjects. For this Aim, the method of measuring ECIMT will remain constant for the 3 years of the study and will involve the use of visual measurements. The second Specific Aim is to utilize a new edge detection algorithm to measure the ultrasound studies that have already been performed as well as those that would be completed for Specific Aim 1. This method allows measurement of both lumen diameter and ECIMT. This measurement technique will be applied to baseline studies and the last follow-up study. A third aim, although not specifically stated, is to compare the visual and edge-detection method. This will provide a check on the potential for "drift" in the visual measurements made over the course of the study. The subjects for this investigation are currently being followed.